please help me with this: Event Type:ErrorEvent Source:MSExchangeIS Mailbox StoreEvent Category:General Event ID:9690Date:8/2/2007Time:5:00:04 AMUser:N/AComputer:HAMMERHEADDescription:Exchange store 'First Storage Group\Mailbox Store (HAMMERHEAD)': The logical size of this database (the logical size equals the physical size of the .edb file and the .stm file minus the logical free space in each) is 18 GB. This database size has exceeded the size limit of 18 GB. This database will be dismounted immediately. For more information, click http://www.microsoft.com/contentredirect.asp. thank you very much

Yep, your database is full. A quick registry change will get you back up and running. I would recommend raising the database size to about 30-35GB. See this article by Dan Petri: http://www.petri.co.il/change_store_size_limits_ex2003_sp2.htm

thank you very much for your help, my server is running good the error message above was solved. but my event viewer-application still have errors: Event Type:ErrorEvent Source:MSExchangeDSAccessEvent Category:Topology Event ID:2114Date:8/2/2007Time:10:08:43 PMUser:N/AComputer:HAMMERHEADDescription:Process INETINFO.EXE (PID=1668). Topology Discovery failed, error 0x80040952. For more information, click http://www.microsoft.com/contentredirect.asp. Event Type:ErrorEvent Source:MSExchangeDSAccessEvent Category:Topology Event ID:2103Date:8/2/2007Time:10:02:48 PMUser:N/AComputer:HAMMERHEADDescription:Process MAD.EXE (PID=2816). All Global Catalog Servers in use are not responding: HAMMERHEAD.seacrest.com For more information, click http://www.microsoft.com/contentredirect.asp. Event Type:ErrorEvent Source:MSExchangeALEvent Category:Service Control Event ID:8250Date:8/2/2007Time:10:02:45 PMUser:N/AComputer:HAMMERHEADDescription:The Win32 API call 'DsGetDCNameW' returned error code [0x862] The specified component could not be found in the configuration information. The service could not be initialized. Make sure that the operating system was installed properly. For more information, click http://www.microsoft.com/contentredirect.asp. Event Type:ErrorEvent Source:MSExchangeALEvent Category:LDAP Operations Event ID:8026Date:8/2/2007Time:10:02:45 PMUser:N/AComputer:HAMMERHEADDescription:LDAP Bind was unsuccessful on directory HAMMERHEAD for distinguished name ''. Directory returned error:[0x51] Server Down. DC=seacrest,DC=com For more information, click http://www.microsoft.com/contentredirect.asp. hope you can help me again with these problem. thanks again

Check out your domain controller HAMMERHEAD. Is that your only DC? Has this system been rebooted lately?